Frans-sabinene hydrate

The short synthesis of (+)-frans-sabinene hydrate, an important flavor chemical found in a variety of essential oils from mint and herbs, was developed by C.C. Galopin. The key intermediate of the synthetic sequence was 3-isopropyl-2-cyclopentenone. Initially a Nazarov cyclization of a dienone substrate was attempted for the synthesis of this compound, but the cyclization did not take place under a variety of conditions. For this reason, a sequential Stetter reactionlintramolecular aldol condensation approach was successfully implemented. 

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